Top-seeded United States and No. 2 seed Poland will meet Sunday in the United Cup final in Sydney.

Coco Gauff and Taylor Fritz topped the Czech team of Karolina Muchova and Tomas Machac on Saturday to advance. Gauff was a 6-1, 6-4 winner; Fritz took the victory when Machac, up a set at 7-6 (4), 5-6 abruptly retired.

Machac, serving at 5-5, lost serve in a love game to drop his third consecutive game, then called it quits. Fritz said in his on-court interview that Machac reported he was cramping.

Poland advanced to its second consecutive World Cup final behind Iga Swiatek and Hubert Hurkacz, who swept Kazakhstan in singles.

The latter put Poland in the lead with his 6-3, 6-2 win over Alexander Shevchenko in 58 minutes. In group play at the mixed-team event. Hurkacz lost both of his singles matches.

And both times, he was bolstered by World No. 2 Swiatek, who on Saturday vanquished rival Elena Rybakina 7-6 (5), 6-4. Rybakina, the 2022 Wimbledon champion, had beaten Swiatek in four of their six career matches.

Swiatek moved to 12-1 in singles at the United Cup.

Brisbane International

Reilly Opelka will be looking for his first ATP Tour win since 2022 when he faces Czech Jiri Lehecka for the title in Australia.

The 6-foot-11 Opelka bested 6-8 Giovanni Mpetshi Perricard of France 6-3, 7-6 (4) to advance. The pair of big servers combined for 22 aces and both won points on 70 percent of their serves.

Lehecka was up a set and tied 4-4 when Grigor Dimitrov of Bulgaria, the No. 2 seed, retired with an injury. Dimitrov was in the quest for a third title in Brisbane.

Hong Kong Open

Kei Nishikori of Japan advanced to his first ATP Tour final in six years when Juncheng Shang of China was forced to retire from their semifinal match due to illness.

Nishikori was up 4-3 at the time. His last tour victory came in Brisbane in 2019.

In the final, the 35-year-old will meet Alexandre Muller of France, who is in search of his first tour title. He defeated Jaume Munar of Spain 4-6, 7-6 (5), 6-4 despite 44 unforced errors against 27 winners.

–Field Level Media